U.S. Secretary of State John Kerry said on Monday there was "finite" time for talks between Iran and world powers on its disputed nuclear program to bear fruit, but gave no hint how long Washington may be willing to negotiate.

Israel, Iran's arch-enemy and convinced Tehran is secretly trying to develop nuclear weapons, has grown impatient with the protracted talks and has threatened pre-emptive war against Tehran if it deems diplomacy ultimately futile.

Kerry's sentiment was largely echoed by Saudi Foreign Minister Prince Saud al-Faisal, who said that the negotiations cannot be endless like the debates of philosophers over how many angels can fit on the head of a pin.

"There is a finite amount of time," Kerry, in the Saudi capital Riyadh on his first overseas trip as the top U.S. diplomat, said of the talks between a group of six world powers and Tehran, Saudi Arabia's main regional adversary.

Kerry was speaking at a news conference with Prince Saud al-Faisal, who suggested Iran was not showing enough seriousness about the discussions, which he said "cannot go on forever".

Iran was positive last week after talks with the powers in Kazakhstan about its nuclear work ended with an agreement to meet again. But Western officials said it had yet to do anything concrete to allay their concerns about its nuclear aspirations.

The United States, China, France, Russia, Britain and Germany offered modest relief from economic sanctions in return for Iran reining in its most sensitive nuclear activity but made clear that no breakthrough was in the offing quickly.

"We can't be like the philosophers who keep talking about how many angels a pinhead can hold," Prince Saud al-Faisal said.

"They (the Iranians) have not proved to anybody the urgency in their negotiation," he said. "They reach common understanding only on issues that require further negotiation. And so this is what (has) worried us."

The United States and many of its allies suspect Iran may be using its civil nuclear program as a cover to develop atomic weapons, a possibility that Israel, which is regarded as the Middle East's only nuclear power, sees as a mortal threat.

The possibility also deeply disturbs many Arab countries in the Gulf who, some analysts say, could choose to pursue their own nuclear programs if Iran were to acquire an atomic bomb, leading to a destabilizing arms race.

In Vienna on Monday, the UN nuclear watchdog raised pressure on Iran to finally address suspicions that it has sought to design an atomic bomb, calling for swift inspector access to a military base where relevant explosives tests are believed to have been carried out.

During his visit to Riyah, Kerry will meet Palestinian President Mahmoud Abbas for unplanned talks. The lunch meeting, which was added to Kerry's schedule at the last-minute on Monday morning, will focus on efforts to resume the diplomatic process between Israel and the Palestinians.

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Kerry, the only 'finite amount of time' applies on how long Israel will
be able to last if it continues with it's crimes agaist the
Palestinians. The anti-American and anti-Israel wave is growing larger
each day and the 'finite amount of time' is coming for America and it's
continuous support of criminal leaders like Netanyahu. Kerry, you should
be worried more about the future of your beloved America than what Iran
is doing.

And I believe together (Egypt &Israel) will be able to police the
middle east and Africa without involving foreign forces.yes I say it
(Egypt &Israel) need to put the past behind their backs and start
building a real strong relationship based on mutual respect not on peace
treaty.can we imagine how powerful and economicaly useful this
relationship will be. Think about it

As because of all all other other faiths did to us Jews if Jews aren't
the ones who save us they're neither the once who saved us and you ALL
KNOW who our saviours and rescuers will be if they're the ones who'd
saved and rescued all us Jew

We are in a crisis so we need a diversion? Almost all terrorist attacks
in the past 20 years came from sunni extremists so let's attack shia
Iran? There must be a hidden agenda to all of this like operation
Gladio in the old days.

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